The philosophes were a group of eighteenth century thinkers, writers, and scientists who were convinced that reason, not prejudice and superstition, is the best guide for individuals and for society. All of them, including Voltaire, had long been working on the huge Encyclopédie: Ou, Dictionnaire raisonné des sciences, des arts et des métiers (1751-1772; 17 volumes of text, 11 volumes of plates; partial translation Selected Essays from the Encyclopedy, 1772; complete translation Encyclopedia, 1965), the completion of which is considered one of the great intellectual achievements of the Enlightenment. However, on September 28, 1752, Frederick the Great of Prussia is said to have suggested to Voltaire that he compile a much shorter book in dictionary form, which would advance the same ideas but would be more accessible. Voltaire promptly got to work, submitting a number of articles to the king during the next several months, but after leaving Frederick’s court, he put the book aside and did not resume work on it until 1762.
In 1764, the book finally appeared. Published anonymously in Geneva under the title Dictionnaire philosophique portatif, it consisted of seventy-three articles. Voltaire was wise not to claim authorship; the book was burned in Geneva, at The Hague, and in Paris, besides being proscribed by the Holy Office in Rome. However, its popularity can be judged by the fact that it was reprinted three times under the same title, with numerous revisions and additions, until in 1769 it appeared as a two-volume edition entitled La Raison par alphabet (reason by alphabet), which contained 120 articles, including the long imaginary dialogue “A, B, C.” The 1769 edition, reprinted as Dictionnaire philosophique, is considered the final and complete version of the work. Peter Gay’s translation (Philosophical Dictionary, 1962) was the first complete, authentic edition available in English.